Dynamic digital communication system control

• US 9,843,348 B2
• Filed: 10/07/2015
• Issued: 12/12/2017
• Est. Priority Date: 06/01/2001
• Status: Expired due to Fees

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Ginis, Georgios, Yu, Wei, Zeng, Chaohuang, Cioffi, John M.
• Primary Examiner(s): Corrielus, Jean B
• Application Number:
  US14/877,720
• Publication Number:
  US 20160072532A1
• Time in Patent Office: 797 Days
• CPC Class Codes: H04B 1/10 Means associated with receiver for limiting or suppressing noise or interference
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04B 1/1081 Reduction of multipath noise by equalising H04B7/005
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04B 2001/1045 Adjacent-channel interference
• CPC Class Codes: H04B 3/32 Reducing cross-talk, e.g. by compensating
• CPC Class Codes: H04B 3/46 Monitoring; Testing
• CPC Class Codes: H04B 3/466 Testing attenuation in combination with at least one of group delay and phase shift
• CPC Class Codes: H04B 3/487 Testing crosstalk effects
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04L 7/0016 correction of synchronization errors
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data

Abstract

Control of a digital communication system having a plurality of communication lines on which signals are transmitted and received is implemented using a variety of methods and systems. According to one embodiment of the present invention, a method is implemented where the signals are affected by interference during transmission and each of the communication lines has at least one transmitter and at least one receiver. A model is created of the interference characteristics due to the signals carried on the communication lines. Interference characteristics for a line are determined based on the model and actual signals carried on other communication lines different from the line for which the characteristics are being determined. Actual interference is compensated for on the communication line using the determined interference characteristics.

Claims

1. A method of controlling a digital communication system having a plurality of communication channels on which transmissions of signals are communicated by the signals being transmitted and received, the signals being affected by crosstalk interference during transmission, each of the communication channels being used by users and each user having at least one transmitter and at least one receiver, the method comprising the steps of:

collecting information about the channel, signal and far-end crosstalk interference characteristics of the communication channels;

in response to the collecting, creating a model of the channel, signal and far-end crosstalk interference characteristics of the communication channels; and

synchronizing the transmitted and received signals across multiple transmitters and receivers to permit signal processing using the model to remove far-end crosstalk interference from the signals.

2. The method of claim 1, further including performing the step of signal processing using the model to remove far-end crosstalk interference from the signals, which step is performed either:

prior to the transmissions of the signals;

after reception of the signals;

or both prior to the transmissions of the signals and after reception of the signals.

3. The method of claim 1, wherein the step of synchronizing transmissions of signals includes using at least one of:

block transmission; and

block reception.

4. The method of claim 1, wherein the digital communication system uses multitone transmission and further including performing the step of signal processing using the model to remove far-end crosstalk interference, which step of signal processing is done on a tone by tone basis.

5. The method of claim 1, wherein the step of collecting is performed by a party other than one of the users.

6. The method of claim 1, further including performing the step of signal processing using the model to remove far-end crosstalk interference from the signals, wherein each channel is permitted to transmit and receive signals using a data rate and wherein the step of signal processing using the model to remove far-end interference includes maximizing a weighted sum of the data rates of the plurality of channels.

7. The method of claim 6, wherein the step of maximizing the weighted sum of the data rates of the channels comprises at least one of:

allocating energy to each user for the transmissions of signals;

creating a matrix which allocates energy to each transmitted frequency, tone or subcarrier; and

creating a matrix which allocates energy to a plurality of transmitters.

8. The method of claim 1, further including performing the step of signal processing using the model to remove far-end crosstalk interference from the signals, wherein the signals are sent using a plurality of frequencies and further wherein the step of signal processing using the model includes dynamically adjusting the frequencies used to send the signals.

9. The method of claim 1, further including controlling the digital communication system by allocating a total power to a channel, such that the power is limited by a power constraint applicable to the entire system.

10. The method of claim 1, wherein the digital communication system determines and controls physical layer communications parameters on a communications environment encompassing each of the plurality of communications channels based on an optimization criteria.

11. The method of claim 1, wherein multiple channels support communications with a single user.

12. The method of claim 1, further including performing the step of signal processing using the model to remove far-end crosstalk interference from the signals, wherein the step of signal processing occurs on at least one of:

the at least one transmitter of the user; and

the at least one receiver of the user.

13. The method of claim 1, further including the step of using an explicit feedback method, based on a transformed estimate of the channel state, to derive the model.

14. The method of claim 1, wherein the model of the channel, signal and far-end crosstalk interference characteristics of the communication channels is based on at least one of:

analysis of special symbols that do not carry data sent by the transmitter; and

analysis of symbols carrying data between the transmitter and the receiver of one of the users.

15. The method of claim 13, wherein the at least one transmitter uses the transformed estimate of the channel state to calculate a matrix indicating the configuration of individual frequencies or tones of the transmitted signals.

16. The method of claim 1, further including performing the step of signal processing using the model to remove far-end crosstalk interference from the signals, wherein the signals being transmitted are sent by the plurality of transmitters, and wherein the step of signal processing using the model includes modifying power to each transmitter among the plurality of transmitters.

17. The method of claim 1, wherein the signals being transmitted are also sent using the plurality of transmitters.

18. A method of controlling a digital communication system having a plurality of communication channels on which transmissions of signals are communicated by the signals being transmitted and received, the signals being affected by interference during transmission, each of the communication channels being used by users and each user having at least one transmitter and at least one receiver, the method comprising the steps of:

collecting information about the channel, signal and far-end interference characteristics of the communication channels;

in response to the collecting, creating a model of the channel, signal and far-end interference characteristics of the communication channels; and

synchronizing the transmitted and received signals across multiple transmitters and receivers to permit signal processing using the model to remove far-end crosstalk interference from the signals,

wherein the interference affecting transmission of signals includes crosstalk from communication channels adjacent the communication channel on which at least one of the signals is sent.

19. A method of controlling a digital communication system having a plurality of communication channels on which transmissions of signals are communicated by the signals being transmitted and received, the signals being affected by crosstalk interference during transmission, each of the communication channels being used by users and each user having at least one transmitter and at least one receiver, the method comprising the steps of:

collecting information about the channel, signal and crosstalk interference characteristics of the communication channels;

in response to the collecting, creating a model of the channel, signal and crosstalk interference characteristics of the communication channels;

synchronizing the transmitted and received signals across multiple transmitters and receivers to permit signal processing using the model to remove crosstalk interference from the signals; and

processing the signals using the model to remove crosstalk interference from the signals, wherein the digital communication system uses a multifrequency communications system and the step of processing the signals using the model is done on a frequency-by-frequency basis.